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Making Use Of Old LCDs?
Posted by
simoniker
on Wed Apr 14, 2004 07:32 PM
from the screens-of-rage dept.
from the screens-of-rage dept.
phorm writes "Not so long ago, higher-definition LCD's used to be quite hard to come by, with laptops and other hardware tending to use old non-TFT-style LCD's which ugly bleeding colors and poor refresh. Nowadays, almost everything has a nice TFT (Thin-film-transistor) display, including laptops, PDA's, digital camera, and often even cellphones. However, not all of these devices are as dependable as they once were, and many of them end up as little more than paperweights. With TFT-LCD's by themselves still being somewhat of a pricey commodity, is there any way to salvage and use these parts for home projects? I personally have an 8" notebook display, and a 1.5" digital camera LCD which are just begging to be recycled as something useful such as a projector component, status display, or something else useful. So far I've had little luck discovering a way to get these components to work outside of the original hardware, so I was wondering if any enterprising hardware-nerds on Slashdot have had better luck than I and could offer a few pointers. Are these components doomed to end up in a landfill, or can somebody offer a way to make them useful again?"
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Making Use Of Old LCDs?
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You could build a video projector (Score:5, Informative)
(http://slashdot.org/)
Re:You could build a video projector (Score:5, Insightful)
(Last Journal: Thursday February 16 2006, @06:22PM)
Re:You could build a video projector (Score:5, Interesting)
(http://slashdot.org/)
I have a DIY PJ built from a multimedia LCD and a overhead projector. Its just 640 x480 but at 5 foot wide it looks better than some rear projection screens I have seen. YMMV
Re:You could build a video projector (Score:5, Interesting)
Actually, since it's an analogue signal, the "effective" horizontal resolution of television signals is limited only by the bandwidth of the luminance and chroma circuits of your receiver/TV and tends to be much higher than the popular 768x576 (PAL/SECAM, 50i) and 640x480 (NTSC, 60i) resolutions offered on capture cards.
Those resolutions were chosen to maintain the 4:3 aspect ratio used on computer monitors based on the number of "useful" lines in the signal (the rest of the lines are used for framing of the front-porch/back-porch and digital data like Teletext).
The 720x480 NTSC resolution made available on some cards makes use of some of this extra resolution, but confuses a number of players because the aspect ratio written in the .AVI/.MPEG streams aren't handled reliably (by either capture or playback software it seems, although some do it better than others).
Thanks (Score:5, Informative)
(Last Journal: Saturday April 15 2006, @06:56AM)
Thanks for setting him straight, I was looking at his post wondering what planet he was from.
You should have also included the fact that interlacing is an accepted (evil?) on the analog world and is still a big thorn in the digital community. That little "i" or "p" in those resolution numbers is a big trade off. Computer monitors use progressive scanning almost always, and that is the way it should be.
Television has fought so many format wars that the battle lines are still being drawn. For example this week they are holding NAB (National Association of Broadcasters) in Las Vegas.
Every single inch of convention space is taken up by the broadcast divisions of the big companys and the 'mom and pop' vendors all competing for your attention for five solid days.
Now I am rambling but I will leave you with this: The Las Vegas hotels hate this convention with a passion. Because the entire thing is populated by people that are so smart that they know the odds inside and out.
Re:You could build a video projector (Score:5, Informative)
(http://www.allappropriatetech.com/)
NTSC is the equiv of 320x240 at 30fps
Almost right. The part you were closest on was 30fps (actually 29.97), which is close enough. The X resolution varies, but in most circumstances is somewhere around 300, so you are right there, too. The Y resolution is 480, which is double what you were saying.
The X resolution depends on what your transmission medium is. Basic, composit NTSC requires that all of the luma information be lower in frequency than the 3.58MHz Croma subcarrier. This subcarrier is going to have a content bandwidth of about 1/2 the Luma data, and therefore a physical bandwidth equal to the luma data. Half that bandwidth will be below the subcarrier, the other half above, so we can assume that the space below the 3.58 carrier is 1/3 croma, 2/3 luma.
Since luma defines the basic resolution, this puts our dot clock at a maximum of about 2.4MHz. Not a lot, granted. If we keep it simple, and divide this by the 262 lines per field (remember, this is an interlaced image) and 59.94 fields per second, we get only about 152 waves per line, or 305 pixels.
There are special cases, however, that need to be noted.
If the signal is sent such that the luma and croma data don't intermingle (S-Video), then the X resoltion can go very high indeed. In fact, there is no real limit here. A 720x480 image is not at all out of the question, with the simple understanding that the croma resolution is going to be only 150 pixels or so, because the croma data are still carried on a 3.58MHz subcarrier (although all of the bandwidth is available, not necessarily constrained by the need not to collide with the luma or audio carriers.... whether or not it is used is another matter). DTV at standard definition, digital cable, digital satellite and DVD all bring us this.
Lastly, component video takes the gloves off. Since we are no longer modulating our croma data, instead sending it as its original two components (Pb and Pr), they, too, can be run at any resolution. Fact is, they are usually run at 1/2 to 1/4 the resolution of the Luma (Y) data, but they don't necessarily need to be. The reason they usually are is that DV and MPEG don't record the croma data at full resolution.
Of course, component video has the additional advantage of being able to support other resolutions. Composite and S-video can not do this because they depend on a fixed-frequency croma carrier.
Re:You could build a video projector (Score:5, Funny)
OH NO!
Re:POLL (Score:5, Insightful)
(http://www.ferion.net/ | Last Journal: Monday May 06 2002, @02:16AM)
No.
Seriously, there's nothing wrong in posting this question to a group of geeks like us. Interesting results can develop, and discussion is usually a good thing. Perhaps people who haven't considered recycling LCDs will be inspired, you never know.
Quitcherbitchen.
Re:POLL (Score:5, Funny)
(http://www.perlstorm.net/)
Great Uses (Score:5, Interesting)
(http://www.individualthought.net/)
Attach to side of monitor for a small second monitor
Write a linux driver to interface directly with the lcd, and GPL it, along with specs.
I *would* imagine you could come up with a variety of uses, since you are a
Way to make them useful again (Score:5, Interesting)
(http://phorm.phormix.com/ | Last Journal: Monday May 19 2003, @12:08PM)
Re:Way to make them useful again (Score:5, Informative)
(http://slashdot.org/~BrianRaker | Last Journal: Sunday June 01 2003, @05:56AM)
LCD use (Score:5, Funny)
(http://homepage.mac.com/inertia186/iblog/ | Last Journal: Monday February 09 2004, @08:06PM)
Re:LCD use (Score:4, Informative)
an idea (Score:5, Funny)
LCDs are difficult (Score:5, Informative)
You can get controllers for many laptop screens, however they only work with specific screens. Say maybe 2-8 out of 300 can work with a particular controller. Most controllers need to have their BIOS programmed and that's usually done out of the factory for specific applications.
On top of that you need to supply your own inverter, any special or propriatory cables or connectors, a power supply, and housing.
This is doable, but expensive.
99% of the time you'd get a better, cheaper, newer LCD display somewere else then trying to build a display out of some random LCD screen.
Better off getting a retail version, or buying a kit from a place like EarthLCD.
Yeah but... (Score:5, Funny)
Lovely screens...
And I *know* /. is just rife with old tyme hackers - folks with C in the heart and solder burns on their fingers (it's just those rogue 3 or 4 who actually use *windows* (spit, cough, hork)).
So who here HASN'T etched a circuit board (analog, digital, no matter)? Anyone? - see. Nobody. All l33t h@x0rs.
So fess up, how do I take apart my Powerbook 180 and get it to work with a Radeon card so I can stuff it into my Kaypro "Portable" case and bring it to Usenix with a dual Athlon64 mobo inside (the power supply in that box is HUGE).
Re:Yeah but... (Score:4, Interesting)
(Last Journal: Tuesday June 27 2006, @08:05AM)
Turn them into digital picture frames. This gentleman turned his PowerBook 100 into a Digital Picture Frame [utoronto.ca] for relatively little cost. If I had a leftover PowerBook that would be one of my first projects.
Re:Yeah but... (Score:4, Insightful)
(re solder burns: there's the occasional touch hot component - there's also been the "sit on the side of a stage with a part held against my thigh with a foot" kinda emergency work.
Burns from the iron? Never. er, 'warmth' from the thing BEING soldered - yeah.
Engineers get to sit in at a clean bench doing work that's been reviewed in meetings by committees.
Real hackers get to solder in a circuit after cutting open the cable casing to get to the wires we need :)
But the windows users won't know what we're talking about, so I'll quit.
Whole machine as Linux + X or ASCII terminal (Score:5, Interesting)
(Last Journal: Wednesday March 02 2005, @11:08PM)
Similarly, if you've got a laptop that's too lame for that, you might still be able to run Windows 3.1 and hyperterm on it, so you've got a scrolling ASCII display for data you feed it on the RS232 port, or maybe VNC running at 112 kbps. It's not your hot-stuff gamez box, but it's enough to display status information, and the great thing about a 386/25 is that you can be Entirely Fearless about performaing dangerous operations on it because there's really no downside risk :-)
PDAs can often run communications programs as well, so you can use the RS232 port to feed them ASCII streams to display. That Palm3 stand can sit neatly on top of your main PC, showing you whatever information you think is interesting in whatever font size you can read. Maybe it's just a clock and weather forecast and network intrusion detection display ("It's 3:32pm, 37 degrees outside, pollen count high, Virus of the Day is Netsky.U".)
Re:Whole machine as Linux + X or ASCII terminal (Score:4, Interesting)
The parent poster wrote:
What more do you need? ;)
Btw, 486-586 era laptops make kick-ass x86 firewalls. Energy consumption is a lot better then a desktop, and they tend to be compact, with a built-in keyboard and video. 2 PCMCIA/Cardbus NICs and you're set.
How to connect them? (Score:5, Insightful)
(http://www.nikola.novak.net/)
Finding specifications (Score:5, Informative)
(http://www.gnaa.us/)
Is going to be your biggest problem. I've had some EPSON-made TFT lcds from cellphones that even epson refused to give me datasheets to - most cellphone LCDs are custom jobs for each specific manufacturer, and they will not be telling you any information about them.
You are better off trashing the screens you got and ordering some cheap LCDs from a place like http://www.mp3playerstore.com/stuff_you_need/speci al/index.html [mp3playerstore.com] and connecting it to your car mp3/dvd/player whatever.
Re:Finding specifications (Score:5, Insightful)
(Last Journal: Tuesday September 18, @11:59PM)
LCD Wiring (Score:3, Informative)
HD44780 LCD Wiring Guide [moddershq.net]
Re:LCD Wiring (Score:5, Informative)
(http://www.macetech.com/ | Last Journal: Monday February 16 2004, @01:44PM)
The real question, interfacing TFT displays, is a wild goose chase. Without the datasheets, an appropriate controller chip, and a good understanding of how to get configurations into said chip, you're not going to get it to work. Some converter boards do exist, but they cost a couple hundred dollars and support only a few LCD panels.
Your best bet at using a given LCD panel is to find the part number, then try to locate a single-board computer that has a personality module for it. This still isn't going to be a cheap solution.
My preferred use: neat pressure-sensitive coaster.
Re:What about display for computer? (Score:5, Funny)
(http://www.macetech.com/ | Last Journal: Monday February 16 2004, @01:44PM)
Dear Ask Slashdot:
A few days ago, my uncle gave me an old John Deere tractor, which is pretty much shot except for the engine. It seems a shame to waste a perfectly good engine, so I was wondering if I could take it out and hook it into my VW Jetta somehow. I know that the engine turns when you put liquid stuff into it and run the starter, so it should be able to work in my Jetta too. I did a Google search for "engine" but didn't find what I was looking for in the first ten results. Could you tell me how to accomplish this task? I only want to spend $20 or less, and only want to use a flat-point screwdriver and a cigar box full of old rusty bolts. Thanks!
Re:What about display for computer? (Score:5, Funny)
Re:What about display for computer? (Score:5, Funny)
(http://slashdot.org/ | Last Journal: Friday May 07 2004, @03:22PM)
(1) Take the engine out of the Jetta. You
probably want to remove the hood since the Deere
engine won't fit very well with the hood on.
(2) Put the deere engine into the engine compartment
of the Jetta. Points to observe here include (a)
make sure to align the PTO of the Deere with the
transmission connector. (b) If they don't match
as is likely, you can wedge a bolt or two into the
gap, so that they interlock. No hammer? I bet you
can find a rock. Just whack on it with a rock until
the bolt(s) are truly wedged. If the Deere PTO is
too big, rather than too small, rub it with a rock
until it is too small.
(3) Strap the engine firmly into place. Hook up
the fuel line and ignition electronics. Fuel line
is trivial, with some rubber tubing, but for
ignition electronics you have to match the wires.
I suggest just connecting all the red outputs to
the red input, black to black, etc. Or else read
a book. As for strapping, some old belts or a dog
chain you aren't using can do wonders.
(4) Be prepared for some mild vibration when you
start the engine. Some rubber to use for shims
can be helpful here. The upside is that if the
vibration is strong enough, even without a good
connection to the transmission, the Jetta is
light enough so that it will move around just due
to brownian motion.
(5) You're ready to do some travelin'!
I replaced the pedal assembly on my BMX bike with
a pulse-jet in about 2 hours. linky linky [pulse-jets.com].
But I want to try a DK8 [blueyonder.co.uk]
when I can find a cigar box full of rusty bolts.
Anyhow, I'm sure you can do the Deere in half
that time, as long as no rock-rubbing is required.
Good luck!
Misc projects (Score:4, Informative)
(http://www.slashdot.org/~lukewarmfusion/journal/ | Last Journal: Tuesday August 02 2005, @02:49PM)
Front-door camera/surveillance system
Mount a TV screen in the bathroom
LCD Picture frame (search Slashdot for this one)
Mount an LCD in your PC case (front or side)
Difficult, but possible (Score:5, Informative)
Check here [earthlcd.com] for some LCD controllers and tips on how to put it together. The problem is that the controllers often cost as much or more than a cheap LCD by itself.
Save the lamp! (Score:5, Informative)
(http://www.thejemreport.com/)
Save the screens for the CCFL lamps that illuminate them. That way when you have to replace such a tube when it wears out or breaks in your working replacement device, you will have a means of repairing it.
CCFL (cold cathod fluorescent lamps) have a life of anywhere between 15,000 and 50,000 hours and most will lose half of their brightness after roughly half of its lifespan. They're also made of thin glass and are easily broken. If you break a CCFL tube you will probably not be able to buy a replacement and even though the tube only costs a few dollars you will have to replace the entire LCD screen at a cost of hundreds of dollars (in a laptop system).
So yeah, keep them for parts... mainly the lamp.
-JemRe:Save the lamp! (Score:5, Informative)
(http://timgray.blogspot.com/)
they usually have lots of CCFL tubes in different sizes...
those parts are EASY to find if you know where and what to look for.
Immediate ATTN required! (Score:5, Funny)
(http://www.rogertheshrubber.net/)
Please reply most immediately so the shipping details can be worked out, I can accept western union payments at this time, but not paypal as the bankrupcy people will find out! I await your reply so these sad little orphaned LCD monitors can be given new life.
Re:Immediate ATTN required! (Score:4, Funny)
Mr. Darl McBride
Shifty Law-Abusing Moron, Recently Named Nigerian Prince
Recycle (Score:5, Funny)
Link... (Score:4, Informative)
http://www.eio.com/lcdconnect.htm [eio.com]
google cache: href=http://www.google.co.uk/search?q=cache:Ily0Q
It's not been updated in a while, but the summary goes: You need to buy a controller, the one that came with the device won't do. They cost more than an lcd screen itself, so unless you're desperate to recycle, you might as well buy.
As for ideas what to do; I always thought i'd be cool to have a little display of system statistics cpu/ram/disk usage, maybe any new emails that have arrived - basically most of the features that superkaramba gives you, except you'd be able to see it when running full screen apps.
Good Luck. (Score:5, Informative)
(http://slashdot.org/ | Last Journal: Saturday February 15 2003, @02:04AM)
Basically, without some rather advanced electronics skills, you're SOL.
Oh, and don't just hook up a display's power without providing the proper clock signals ... the liquid crystals will decompose through electrolysis.
old pda screens are great.... (Score:4, Insightful)
(http://timgray.blogspot.com/)
fortunately the phillips PDA's we have here at work that were retired and left for dead in the back room had the SAME lcd.
3 worthless PDA's equals 3 TS2000 Pronto remotes for dirt.
the problem lies in finding data on the LCD and or an application.. eio.com has lots of color LCD's for dirt that are pretty un-useable as they are custom and no information will be released on them.
Blame the industry (Score:5, Informative)
(http://www.splunge.net/)
Once you've sorted all of that out and your LCD powers up, you will need to interface your video signal. There are not only many different physical connector schemes used in panels, but many pinouts and electrical / timing methods. Not to mention that the panel takes a serial or framed digital signal, while your PC probably emits an analog one (except DVI-D)
Once your panel is lashed up to a host, you would need to convince your OS to drive the panel with a VERY specific set of timings. Remember, this panel is a purely digital device and isn't tolerant of sloppy video or sync signals like the average glass boob is. And of course forget about baseband TV video unless you're prepared to do some scan conversion.
You could make it work. I occasionally have to spec and implement LCDs for projects at work. It's not easy to do even when you have a device designed to drive an LCD. Hell, some of the VIA Mini-ITX boards come with a LVD video output port for driving some panels. But still, you can see that there is more value in that flat panel monitor than just the LCD.
Datasheets galore (Score:4, Informative)
Here's a link, try not to kill yourself (Score:5, Informative)
(http://www.forum2000.org/Gateway/www.slashdot.org)
Lightbox for photography (Score:5, Insightful)
E-Bay it (Score:4, Interesting)
(http://www.fred08.com/)
Yes, those LCDs are quite profitable if you know were to look.
even more links/ideas (Score:5, Informative)
(Last Journal: Tuesday February 22 2005, @01:21AM)
so those might not be so hot unless you've got TV/NTSC out on your video card. LCDs with VGA controllers can be
found but are much more expensive. many vendors prefer to deal in volume only, so don't expect
too much help, or fast email replies.
i'd have to agree with some of the other posters; you might want to get an old thinkpad and butcher it a bit if you need
to get more resolution than TV(less than 640x480 IIRC, maybe 425?)
anyway, here are some other novel uses:
1 - get a bunch and make a shutter for a window in a car, sunroom, etc.
2 - get a bunch and make Art, i.e. a large random color/shape thingy to hang on a wall
3 - use it as a shutter in your front door for inspecting IDs
4 - use one as a digital shutter for a darkroom enlarger(for those still using film, that is.)
5 - make your own car/truck rear-view screen(needs a vid-cam)
OCH LCD MicroView Review [2fastcpu.com]
LCD Mod [soulsend.com]
Extreme Overclocking-5in LCD Ultra-Thin Video Module Review - Page: 4 - Tweaking PC Hardware To The Max [extremeoverclocking.com]
Mikhailtech [mikhailtech.com]
5 Color LCD Mod [l33tpeeps.com]
Mini LCD Monitor Review - Amdmb.com [amdmb.com]
Computer Compatible Small Format LCD Monitors [millertech.com]
EarthLCD Home Page [earthlcd.com]
Candescent: ThinCRT Showcase [candescent.com]
Caltron Industries, Inc. [caltronind.com]
Caltron Industries, Inc. [caltronind.com]
Timeline, Inc. LCD Displays [timeline-inc.com]
6a3 5 X-Bri PAL-NTSC [visiontouch.com]
6 TFT LCD Module Kits [visiontouch.com]
5 mobile lcd display [208.21.161.76]
Mobile LCD Modules [radiomancaraudio.com]
Pyle PLVWHR56M<br>5.6 Mobile Video LCD Monitor<br><img> [millionbuy.com]
Parts Express: Browsing LCD 4 VIDEO MODULE [partsexpress.com]
LCD Projectors, LCD, LCD Monitors, LCD Displays, LCD Panels, LCD Screens, Small LCD Monitors, LCD Flat Panel Displays, Resistive LCD Touch Screens [gorilla.net]
flat panel displays from Spire Controls [spirecontrols.com]
Controllers are NOT unobtanium (Score:5, Informative)
(Last Journal: Thursday July 24 2003, @04:07AM)
Yes, it would take some time. Yes, it would be a challenge. But it's a long way from impossible, and all it takes is a handfull of off the shelf parts - AD even has application notes. Combine one of their evalkits with the specs for, say, an IBM TFT display (13.3" 1024x768 units [eio.com] are like 80 bucks on ebay and 14" 1280x1024 units [eio.com] are only slightly more) and I''ll wager you could not only make your own display circuit, you could probably offer the pcboards after you design it and make enough money to buy a proper projection hdtv.
Let us know when you have the circuit - I want about four of'em.
Re:mm... (Score:4, Funny)
bingo.
I looked into this sometime ago (Score:4, Informative)
(Last Journal: Friday August 17, @05:34AM)
The LCD on my laptop had the controller on the motherboard. Not in the laptop itself. So it was not a case of figuring out the leads on the ribbon cable but rather of building my own controller for the LCD.
Safe to say that was a little bit more complicated then I could handle. From the posts so far this seems to be the general conclusion. LCD screens are not cost effective to salvage.
Then again a small screen ain't all that expensive anymore and we have come an awfull long way in resolution, speed and viewing angle.
For those with a working laptop, what could work is modding your laptop. break its back so that the base is behind the LCD and you have a thick screen you can mount. or maybe you can lenghten the ribbon cable. But basically you need the PC it came with to control the LCD.